Viewport resizer

Responsive design bookmarklet

Responsive design testing toolIt only takes 2 seconds!

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Viewport resizer is a browser-based tool to test any website’s responsiveness.
Just save the bookmarklet, go to the page you want to test, click on your created bookmarklet and
check all kinds of screen resolutions of the page.

The smartest way to share your defined environment of devices and breakpoints directly with your team and client.

This bookmarklet should not replace a real device simulation. It rather helps you, your team and client testing
statuses, transitions, text length etc. throughout different device types.